linux-kernel - Re: Arches that don't support PREEMPT

lists.openwall.net		lists / announce owl-users owl-dev john-users john-dev passwdqc-users yescrypt popa3d-users / oss-security kernel-hardening musl sabotage tlsify passwords / crypt-dev xvendor / Bugtraq Full-Disclosure linux-kernel linux-netdev linux-ext4 linux-hardening linux-cve-announce PHC
Open Source and information security mailing list archives

Hash Suite: Windows password security audit tool. GUI, reports in PDF.

[<prev] [next>] [<thread-prev] [thread-next>] [day] [month] [year] [list]

Message-ID: <87edituu6m.ffs@tglx>
Date:   Wed, 20 Sep 2023 10:26:25 +0200
From:   Thomas Gleixner <tglx@...utronix.de>
To:     Linus Torvalds <torvalds@...ux-foundation.org>,
        John Paul Adrian Glaubitz <glaubitz@...sik.fu-berlin.de>
Cc:     Peter Zijlstra <peterz@...radead.org>,
        Matthew Wilcox <willy@...radead.org>,
        Ankur Arora <ankur.a.arora@...cle.com>,
        linux-kernel@...r.kernel.org, linux-mm@...ck.org, x86@...nel.org,
        akpm@...ux-foundation.org, luto@...nel.org, bp@...en8.de,
        dave.hansen@...ux.intel.com, hpa@...or.com, mingo@...hat.com,
        juri.lelli@...hat.com, vincent.guittot@...aro.org, mgorman@...e.de,
        rostedt@...dmis.org, jon.grimm@....com, bharata@....com,
        raghavendra.kt@....com, boris.ostrovsky@...cle.com,
        konrad.wilk@...cle.com, jgross@...e.com, andrew.cooper3@...rix.com,
        Geert Uytterhoeven <geert@...ux-m68k.org>,
        linux-m68k@...ts.linux-m68k.org,
        Richard Weinberger <richard@....at>,
        Anton Ivanov <anton.ivanov@...bridgegreys.com>,
        Johannes Berg <johannes@...solutions.net>,
        linux-um@...ts.infradead.org, Brian Cain <bcain@...cinc.com>,
        linux-hexagon@...r.kernel.org,
        Richard Henderson <richard.henderson@...aro.org>,
        Ivan Kokshaysky <ink@...assic.park.msu.ru>,
        Matt Turner <mattst88@...il.com>, linux-alpha@...r.kernel.org
Subject: Re: Arches that don't support PREEMPT

On Tue, Sep 19 2023 at 10:25, Linus Torvalds wrote:
> PeterZ mentioned the generic entry code, which does this for the entry
> path. But it actually goes much deeper: just do a
>
>     git grep preempt_disable arch/x86/kernel
>
> and then do the same for some other architectures.
>
> Looking at alpha, for example, there *are* hits for it, so at least
> some of the code there clearly *tries* to do it. But does it cover all
> the required parts? If it's never been tested, I'd be surprised if
> it's all just ready to go.

Interestingly enough m68k has zero instances, but it supports PREEMPT on
the COLDFIRE subarchitecture...